MIS contact structure with metal oxide conductor

A method of manufacturing a metal-insulator-semiconductor electrical contact, comprising:

• forming an n-type doped region of a semiconductor layer,
• depositing a layer of an insulating material over the n-type doped region of the semiconductor layer;
• defining a contact window and etching a hole through the layer of the insulating material to expose a surface of the n-type doped region of the semiconductor layer;
• cleaning the exposed surface of the n-type doped region of the semiconductor layer;
• forming a first layer of a first metal oxide on the exposed surface of the n-type doped region of the semiconductor layer;
• depositing a second layer of a second metal oxide different than the first metal oxide and that is electrically conductive over the first layer of the first metal oxide;
• depositing a layer of an adhesion or barrier metal and filling the hole with a bulk metal to form a metal plug.

A method of manufacturing a metal-insulator-semiconductor electrical contact, comprising:

• forming an n-type doped region of a semiconductor layer,
• depositing a layer of an insulating material over the n-type doped region of the semiconductor layer;
• defining a contact window and etching a hole through the layer of insulating material to expose a surface of the n-type doped region of the semiconductor layer;
• cleaning the exposed surface of the n-type doped region of the semiconductor layer;
• forming a first layer of a first metal oxide on the exposed surface of the n-type doped semiconductor region of the semiconductor layer;
• depositing a second layer of a second metal oxide different than the first metal oxide and that is electrically conductive over the first layer of the first metal oxide;
• depositing a layer of tungsten and filling the hole with tungsten to form a tungsten plug.